FIG. 14 shows a dual clutch assembly 700 from commonly assigned, and therefore, uncitable, United States Patent Application No. 2005/0139442 filed Dec. 23, 2004 and published Jun. 30 2005, which application is incorporated herein by reference. In FIG. 14, clutch housing 702 is connected to outer housing 704. Engine torque is transmitted to housing 704 and transmitted to housing 702. Housing 702 transmits the torque to clutch plates 706. In turn, the clutch plates, when engaged, transmit the torque to carrier 708. Openings in the wall of the carrier are provided for oil flow through the assembly. The rotation of the carrier generates centripetal force that helps to pump oil through the openings. The carrier only rotates when the clutch pack is engaged. For example, axial force is applied to begin to engage plates in the clutch pack. The plates in the clutch pack go through a slippage mode and then fully engage. In parallel, the carrier begins to rotate, rotation increase through the slippage mode, and synchronizes with the engine torque input when the plates fully engage. The greatest amount of heat is generated during the slippage mode and consequently, oil cooling requirements are greatest during the slippage mode. Therefore, cooling requirements are typically greatest at the beginning of the slippage mode. The oil flow would be greater if the pumping action of the carrier were increased during the slippage mode.
Assembly 700 uses lever springs, for example, spring 710, to provide the axial force necessary to engage plates in a clutch pack. Typically, separate fulcrum elements, such as element 712, are used to transfer axial force from the springs to the clutch packs. If the fulcrum were eliminated, the parts count, cost, and complexity of a clutch assembly could be reduced.
Thus, there is a long-felt need for increasing oil flow through a clutch housing while plates in a clutch pack for the housing are slipping. Further, there is a long-felt need for a simplified means of transferring axial force from a lever spring to a clutch pack in a clutch housing.